PARIS 2008: TB vaccine trials announced for Kenya

Photo by el copilotDutch bio-pharma company Crucell NV and the Aeras Global TB Vaccine Foundation have announced the start of a phase 1 clinical trial in Kenya of the jointly developed tuberculosis (TB) vaccine candidate, AERAS-402/Crucell Ad35.

“There are many potential uses of a new TB vaccine. Therefore, it is important to determine a candidate’s safety and immune responses in those who have already been exposed or have had active TB,” Jerald C. Sadoff, MD and President and CEO of Aeras, told delegates at the 39th World Conference on Lung Health in Paris on 17 October after announcing the trials.

“We are pleased to be working with two outstanding organizations in Kenya and South Africa—the Walter Reed Project-Kenya and the University of Cape Town—to move this promising candidate forward in development,” Sadoff said.

The study will be conducted in Kombewa, near Kisumu in Western Kenya with the aim of testing the safety of the candidate in health adults already vaccinated with the Bacille-Calmette Gurin and exposed to TB.

Aeras and Crucell began jointly developing the vaccine candidate in 2004 using Crucell's AdVac vaccine technology and PER.C6 manufacturing technology. A first phase 1 clinical trial launched in October 2006 in Kansas, USA indicated that the vaccine candidate was safe in healthy adults in that country.

The preliminary results of a second study launched in May 2007 were presented at the ‘TB Vaccines for the World' conference in April 2008 and showed both critical arms of the cellular immune system, CD4 and CD8 immune T-cells, were induced and that in those participants who responded, CD8 immune responses were considerably higher than had ever previously been seen in a TB vaccine study.

A third phase 1 study in healthy adults in St. Louis, Missouri was launched in December 2007, focusing on the immunogenicity and safety of two AERAS-402/Crucell Ad35 boost doses administered at three to six month intervals after BCG priming in healthy adults.

“We are very pleased with our continued progress with this next generation TB vaccine,” Dr Jaap Goudsmit, Crucell's Chief Scientific Officer, told delegates at the conference. “The initiation of these two new studies through our fruitful collaboration with Aeras puts us another step closer to our ambition of reducing the global burden of this fatal disease.”

The announcement was met with enthusiasm from some conference delegates, with Lucy Chesire, a Kenyan TB advocate, hailing the companies’ decision to hold the trial in her country.

“I am glad that a high-burdened country like Kenya has been selected in these broader comprehensive efforts in advancing new tools that are urgently required in global TB control efforts, more so in an era where TB-HIV co-infection is a great challenge,” she said.

Crucell and Aeras also announced the start of the first phase 2 study of AERAS-402/Crucell Ad35. The study is being conducted in Cape Town, South Africa by the University of Cape Town Lung Institute in conjunction with the South African Tuberculosis Vaccine Institute (SATVI).

The screening of volunteers has started and immunizations are scheduled to start in the next couple weeks. The candidate will be tested in 82 adults who have had active TB.